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Initial implementation of moist_lapse_rate()

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XANTRONIX 2025-03-05 00:34:23 -05:00
parent b45a6f27c5
commit 0aad130001
1 changed files with 15 additions and 0 deletions
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15
lib/xmet/thermo.py
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@ -1,6 +1,9 @@
LAPSE_RATE_DRY = 9.8 / 1000 # degrees C per km
LAPSE_RATE_MOIST = 4.0 / 1000
def kelvin(c: float) -> float:
return 273.15 + c
def vapor_pressure(dewpoint: float) -> float:
"""
Return the pressure of vapor in a parcel of a given dewpoint.
@ -56,3 +59,15 @@ def lapse(temp: float, delta: float, rate=LAPSE_RATE_DRY) -> float:
given increase in height (in meters).
"""
return temp - (rate * delta)
def moist_lapse_rate(temp: float, dewpoint: float, pressure: float) -> float:
g = 9.8076
Hv = 2501000
r = mixing_ratio(dewpoint, pressure)
Rsd = 287
Rsw = 461.5
Cpd = 1003.5
T = kelvin(temp)
return g * (1 + (Hv * r) / (Rsd * T)) \
/ (Cpd + ((Hv**2 * r) / (Rsw * T**2)))